package com.winning.bdu.collect.jdbc;

import com.alibaba.fastjson.JSON;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import javax.annotation.Resource;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;


/**
 * @Author: yanxf@winning.com.cn
 * @Description: 批量导入工具类
 * @Date 2019/05/15 15:32
 */
@Component
public class BatchInsertUtils {
    private Logger logger = LoggerFactory.getLogger(getClass());

    @Resource
    private JdbcTemplateRepository jdbcTemplateRepository;

    private int defaultSize = 200;

    /**
     * 批量插入数据
     *
     * @param jsonStr json字符串
     * @param tableName 表名
     * @throws Exception
     */
    public void execute(String jsonStr, String tableName) throws Exception {

        List<Map<String,Object>> datas = (List<Map<String, Object>>) JSON.parse(jsonStr);
        execute(datas, tableName, defaultSize);
    }

    /**
     * 批量插入数据
     *
     * @param datas 更新对象集合
     * @param tableName 表名
     * @throws Exception
     */
    public void execute(List<Map<String, Object>> datas, String tableName) throws Exception {

        execute(datas, tableName, defaultSize);
    }

    /**
     * 批量插入数据
     *
     * @param datas 更新对象集合
     * @param tableName 表名
     * @param size  批量sql条数
     */
    public void execute(List<Map<String, Object>> datas, String tableName, int size) throws Exception {

        List<String> batchSQL = buildSQL(datas, tableName, size);

        if (CollectionUtils.isEmpty(batchSQL)) {
            return;
        }
        for (String sql : batchSQL) {
            logger.debug(sql);


            jdbcTemplateRepository.getJdbcTemplate().execute(sql);

        }
    }

    /**
     * 创建批量sql
     *
     * @return
     */
    private List<String> buildSQL(List<Map<String, Object>> datas, String tableName, int splitSize) throws Exception {

        if (CollectionUtils.isEmpty(datas)) {
            return null;
        }
        List<String> batchSQLs = new ArrayList<>();
        Map<String, Object> headerMap = datas.get(0);
        String headerSql = createInsertHeader(tableName, headerMap);
        int dateSize = datas.size();
        int pageNum = 1;
        StringBuilder fieldSb = new StringBuilder();
        Iterator<Map<String, Object>> iterator = datas.iterator();
        for (int i = 0; iterator.hasNext(); i++) {
            int offSet = (dateSize - (splitSize * (pageNum - 1))) > splitSize ? splitSize * pageNum : dateSize;

            fieldSb.append(createInsertValue(iterator.next(), headerMap));
            if ((offSet - 1) == i) {
                String fieldStr = StringUtils.substringBeforeLast(fieldSb.toString(), ",");
                batchSQLs.add(headerSql + fieldStr);
                pageNum++;
                fieldSb.setLength(0);
            }
        }
        return batchSQLs;
    }

    /**
     * 创建取值sql
     *
     * @return
     * @throws Exception
     */
    private StringBuilder createInsertValue(Map<String, Object> dataMap, Map<String, Object> headerMap) throws Exception {

        StringBuilder fieldSb = new StringBuilder("(");

        int index = 1;
        for (Map.Entry<String, Object> entry : headerMap.entrySet()) {

            Object value = dataMap.get(entry.getKey());
            if (value instanceof String) {
                String valuestr = String.valueOf(value);
                valuestr = StringUtils.replaceEach(valuestr, new String[]{"'"}, new String[]{"\\'"});
                fieldSb.append("'").append(valuestr).append("'");
            } else {
                fieldSb.append(value);
            }

            if (index < headerMap.size()) {
                fieldSb.append(",");
            }
            index++;
        }
        fieldSb.append("),");
        return fieldSb;
    }



    /**
     * 创建头部sql
     *
     * @throws Exception
     */
    private String createInsertHeader(String tableName, Map<String, Object> headerMap) throws Exception {

        StringBuilder fieldSb = new StringBuilder();
        headerMap.forEach((key, value) -> fieldSb.append(key + ", "));
        String fieldStr = StringUtils.substringBeforeLast(fieldSb.toString(), ",");
        String headerSql = "INSERT INTO " + StringUtils.uncapitalize(tableName) + "(" + fieldStr + ") VALUES ";
        return headerSql;
    }


}
